What are the required steps to convert base 10 integer
number -11 000 873 787 to signed binary code (in base 2)?
- A signed integer, written in base ten, or a decimal system number, is a number written using the digits 0 through 9 and the sign, which can be positive (+) or negative (-). If positive, the sign is usually not written. A number written in base two, or binary, is a number written using only the digits 0 and 1.
1. Start with the positive version of the number:
|-11 000 873 787| = 11 000 873 787
2. Divide the number repeatedly by 2:
Keep track of each remainder.
Stop when you get a quotient that is equal to zero.
- division = quotient + remainder;
- 11 000 873 787 ÷ 2 = 5 500 436 893 + 1;
- 5 500 436 893 ÷ 2 = 2 750 218 446 + 1;
- 2 750 218 446 ÷ 2 = 1 375 109 223 + 0;
- 1 375 109 223 ÷ 2 = 687 554 611 + 1;
- 687 554 611 ÷ 2 = 343 777 305 + 1;
- 343 777 305 ÷ 2 = 171 888 652 + 1;
- 171 888 652 ÷ 2 = 85 944 326 + 0;
- 85 944 326 ÷ 2 = 42 972 163 + 0;
- 42 972 163 ÷ 2 = 21 486 081 + 1;
- 21 486 081 ÷ 2 = 10 743 040 + 1;
- 10 743 040 ÷ 2 = 5 371 520 + 0;
- 5 371 520 ÷ 2 = 2 685 760 + 0;
- 2 685 760 ÷ 2 = 1 342 880 + 0;
- 1 342 880 ÷ 2 = 671 440 + 0;
- 671 440 ÷ 2 = 335 720 + 0;
- 335 720 ÷ 2 = 167 860 + 0;
- 167 860 ÷ 2 = 83 930 + 0;
- 83 930 ÷ 2 = 41 965 + 0;
- 41 965 ÷ 2 = 20 982 + 1;
- 20 982 ÷ 2 = 10 491 + 0;
- 10 491 ÷ 2 = 5 245 + 1;
- 5 245 ÷ 2 = 2 622 + 1;
- 2 622 ÷ 2 = 1 311 + 0;
- 1 311 ÷ 2 = 655 + 1;
- 655 ÷ 2 = 327 + 1;
- 327 ÷ 2 = 163 + 1;
- 163 ÷ 2 = 81 + 1;
- 81 ÷ 2 = 40 + 1;
- 40 ÷ 2 = 20 + 0;
- 20 ÷ 2 = 10 + 0;
- 10 ÷ 2 = 5 + 0;
- 5 ÷ 2 = 2 + 1;
- 2 ÷ 2 = 1 + 0;
- 1 ÷ 2 = 0 + 1;
3. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
11 000 873 787(10) = 10 1000 1111 1011 0100 0000 0011 0011 1011(2)
4. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 34.
- A signed binary's bit length must be equal to a power of 2, as of:
- 21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32; 26 = 64; ...
- The first bit (the leftmost) is reserved for the sign:
- 0 = positive integer number, 1 = negative integer number
The least number that is:
1) a power of 2
2) and is larger than the actual length, 34,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 64.
5. Get the positive binary computer representation on 64 bits (8 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 64:
11 000 873 787(10) = 0000 0000 0000 0000 0000 0000 0000 0010 1000 1111 1011 0100 0000 0011 0011 1011
6. Get the negative integer number representation:
To get the negative integer number representation on 64 bits (8 Bytes),
... change the first bit (the leftmost), from 0 to 1...
-11 000 873 787(10) Base 10 integer number converted and written as a signed binary code (in base 2):
-11 000 873 787(10) = 1000 0000 0000 0000 0000 0000 0000 0010 1000 1111 1011 0100 0000 0011 0011 1011
Spaces were used to group digits: for binary, by 4, for decimal, by 3.